1. Field of the Invention
The invention relates to a method for the cooling of a shaft furnace fed with liquid or gaseous fuels, for the calcining of limestone, for example, and wherein the fuel passes via hollow beams. Cooling chambers are also provided for passing through a cooling liquid into the shaft furnace chamber.
2. Description of the Prior Art
During the calcining of limestone in shaft furnaces, it is known to install hollow beams in order to be able to distribute the liquid or gaseous fuels as uniformly as possible over the entire cross-section of the combustion zone. During operation, these hollow beams are heated quite highly in known manner so that cooling is advantageous.
From German Pat. No. 1,156,694 it is further known to cool by use of water hollow beams which bring liquid or gaseous fuels into the combustion zone of lime-shaft furnaces. This takes place such that in the side walls of the hollow beams, cooling chambers are constructed which have water flowing therethrough. In this way, the walls of the hollow beams are protected from excessive heating. By this cooling method, the utilizable temperature difference of the cooling liquid, however, is slight, while the temperature difference between the cooling liquid and the interior of the furnace is great. The use of cooling water is appreciable. Besides, high temperature gradients and large material stresses occur in the hollow carriers.